use arena by default in native installation

machine-learning/immich_ml/config.py

@@ -61,6 +61,7 @@ class Settings(BaseSettings):
     request_threads: int = os.cpu_count() or 4
     model_inter_op_threads: int = 0
     model_intra_op_threads: int = 0
+    model_arena: bool = True
     ann: bool = True
     ann_fp16_turbo: bool = False
     ann_tuning_level: int = 2

machine-learning/immich_ml/sessions/ort.py

@@ -123,7 +123,7 @@ class OrtSession:
     @property
     def _sess_options_default(self) -> ort.SessionOptions:
         sess_options = ort.SessionOptions()
-        sess_options.enable_cpu_mem_arena = False
+        sess_options.enable_cpu_mem_arena = settings.model_arena
 
         # avoid thread contention between models
         if settings.model_inter_op_threads > 0: